Evaporator.



o. KRAMER.

BVAPORATOB,

APPLITION FILED JNZ, 1906, 907, 109. v atented Dec. 15, 1908. 2 alHFH'I'q--SHH'Iil.

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o. FALLER. BVAPQRATOR. APPLICATION FILED JAN. 2, 15506. 9G7,09, Patented Dec. 15, 1908.

llNl'llillU aires raras OSCAR FALLER, OF BASEL, SWITZERLAND.

EVAPORATOR.

Specification of Letters Patent.

Patented Dec. 15, 1908.

a, leus. semi No. 294,241.

.To all whom it may concern.'

Be it known that I, Osons FALLER, a citi- Zen of the Republic of Switzerland, 'residing at No. 53 lhiersteiner Allee Basel, in the Canton of Basel, Switzerland, engineer and merchant, have invented a new and useful Improvement in Evaporators, of which the following is a specification.

The present invention relates to evaporators and particularly to an apparatus for the boiling of iinpure liquids or of such liquids as deposit inud, scale or solid substances of any kind during boiling.

The invention is especially suitable for treatment of cellulose prepara-tiens.

The ap aratus consists essentially of an upper andJ a lower receptacle (which may have any desired forni) and of a heating vessel composed of a casing or cylinder adapted to contain thehmiting fluid and having heating tubes arranged at un acute angle to the pcrpendicular, the upper and lower ends whereof are connected to the aforesaid receptacles in such a manner that an uninterrupted cirpulation of the liquid is produced, the liquid rising from the lower receptacie through the tubular heater into the upper receptacle, and descending again through a return pipe to the lower receptacle. As a further precaution against the choking of the .heating tubes by sediment, the upper end of the heater is caused to project appreciably Within the up er receptacle.

t is moreover a feature of this apparatus that only smell quantities of liquid come into contact at any tune with the tubularheating vessel and that these are therein heated and expanded and consequently ascend. The steam bubbles occurring in this asceinling freshly heated current of liquid, which contains in it the impurities or solids separated on heatin or on the form ation of steam, are coi'isequently carried upward with the current at an angle corresponding to the inclination of the tubes and do not rise vertically upwards over the heating vessel. On the contrary the aforesaid steam bubbles'having acquired during their ascent a slopingdirection, due principally to the inclined position of the heating tubes, when. they burst the impurities or solids contained in the thick liquid are scparated, 'and tend (in consequence of their greater specifici-weight) to sink, but they are prevented by vthe sloping position of the the tubes and the sidewise inclination of the cur-L rent from depositing themselves upon the I heating surfaces, and the;v are carried further l by the return current until they collect in the specially provided lower :olla \cting recepita l cle. By this means the lui-ring up or choki ing of the heating tubes is prevented. ri`hat portion of 'the apparatus in which the circullating liquid descends is construeted. wide l enough to cause the specd'of the ilow tobe ,t very slight, and at that pointue new addition f' of heat takes placeA but on the contrary there is a certain amount of cooling. The separated substances have therefore plenty oi opportunity to sink to the bottoni ol' 'the lower receptacle and to collect there. is the approach to the heating surfaces lies above the place where the collecting of the sediment takes place, the liquid passing to the heating surfae is is continuously freed from solid deing apparatus can take place.

rlhe drawing illustrates the invention in two constructional modifications.

Figure l shows a vertical section through a boiler provided with a heater of the kind above `set forthV liig. 2 shouf: a vertical I section. through similar vessel having two heaters arranged opposite to each other.'

rl`hc heating vessel A (Fig. l) comprises a group of heating tubes arranged parallel and at an acute angle with regard to the perpendicular. For the v)urpose of the heating, these tubes are inclosed in a casing within which the heating fluid (st-earn, lire gases and so forth) is caused to circulate. ri`he coniplete apparatus consists of the lower receptacle and collecting tank l, the sloping tubular channel E, the iacketed heater A, the upper receptacle B the liquid inlet G, the heating luid inlets ll and the tapering return pipe C. llie liquid under treatment circulates successively through these receptacles, pfssing upwards from l) to E thence entering the heating tubes A at a and escaping therefrom at the upper ends b of said tubes into the u )perrecepacle B; the return flow of the liquid is through the return pipe C .downwards into-the collectingl tank D, in which the solid materials gravitate towards the outlet F, while the liquid again coni-- inences to ascend through the channel E. In the upper receptacle B the steam bubbles rising from the heated liquid emerging from the tubes of lthe heating vessel A areiinpelled sidewise, parti r through the sidewise circelation of the iquid, and partly by reason of the sloping position of the heating tubes.

posits, so that no clicking of the tubular hea t y heating tubes.

The circulation is indicated in the drawing by means oi the arrows. heater A. is arranged to project into the receptacle B, thereby insuring that no cooling efl'feet can take place at the orifices of the The large tapering return pipe C serves as a connecting sup ort between the upper rece tacle B and t e lower receptacle lj, which atter acts as collector for the separated solid particles or sediment. The deposited substances are removed from the apparatus from time to time through the outlet F. Finally the lower receptacle@ is connected to the lower ends of the tubes in the heater A by nie-ans of the tube E, inclined at an angle opposite to that of the heating tubes.

The primary object of the connection E is to serve as the uptake for the pipes A"and this function may be eilected by varyin the shape of the connection E or even by en arging the receptacle D so as to obtain a direct connect-ion with its upper side orifice and the pipes A thus substantially eliminating the' part E, or in any other sitable manner.

ln the consti-notional modification illustrated in Fig. 2 the parts A and E are constructed in duplicate. The arrangement of each separate heater is identical with that describedwith reference to Fig. 1. The operation ',l'o'f this construction is as follows: The l liquid rising through the tubes of the heaters l A Hows up into thereceptacle B at an angle to the perpendicular as already explained and descends through the centrally arranged connecting tube C, thus reaching again the lower receptacle D, in which the precipitates or solids separated throughout the whole heating operation and circulation collect, and can be removed without coniing into contact with the heaters A.

I claiin- 1. An evaporator for liquids containing solid substances comprising in combination, an upper receptacle, a plurality of upright in( ased tubes having their upper ends within the casing and projecting together therewith into the upper receptacle, said tubes and casing at an acute angle to the vertical axis of the apparatus, a downwardly tapering return tube ol' large dimensions connected at its upper end to the said container and at itslower end to the settling tank, a settling tank beneath the said return tube connected at its upper part with the lower end thereof, and a tubular connection between the said settling tank and the lower ends of the group of iniased heating tubes, said tubular connection inclined at an angle opposite to that ofthe sald heating tubes.

2. ln lcoinbination in circulating appara tus for theteraporation of liquids contain. n0 solid substances and segregation of said solid substances, the upper receptacle B, a

Moreover the ser, 10a

plurality of nearly vertical ncased tubes having their casing inclosing their upper ends and projecting within the said receptacle lj, the dou nwardly tapering return tube C, the cylindrical settling tank D connected at its top to the return pipe C, the inclined supply tubes E connected at their lower ends to the settling tank D and at their enlarged upper ends to the lower ends of the tubes A and so that the angle of inclination of the tubes E is opposite to that of the angle of inclination of the tubes A.

3. An apparatus of the class described comprising a container located at the bottom -of the apparatus and open at the top, a conduit' extending upward from the top opening of said container, a receptacle connected with the upper end of said conduit and extending laterall therefrom, an uptake leading from the si e of said container the crosssection of said, conduit and uptake being relatively large ,so as to prevent any violent motion of the liquid therein, and also to prevent the articles floating dovsn with the liquid in t e conduit and container from be ing sucked into the uptake to any material extent, a set of relatively narrow tubes connecting said uptake with sald receptacle and arranged at a sharply-acute angle to the vertical aris of the apparatus, sa d tubes bein inclined in a d'rection toward the vertica axis of the cond dit at their upper ends, and a heating `iaeket for safd tubes, the sad conduit being spaced from the heating jacket so as to permit it to be exposed to a cooling rrediuin, the said receptacle permitting a dovi nward flow from the upper end of each of said tubes to the said conduit.

4. An evaporator forliquids containing solidsubstances comprising in combination an upper receptacle and lower receptacle, a plurality of upright tubes of relatively small diameters interposed between the said receptacles, means for heating said tubes, said tubes opening directly into the body of liquid containedin the upper receptacle andI extending at` an angle sharply acute with ref'- erencc to the vertical axis of the concentrator iii a direction toward the upper opening of ar'eturn tube, a return tube connecting openings of the inclined tubes being-so cated as to cause theliquid coming therefrom to pass immediately in a downwarduninterru ted direction toward the upper opening of t e return tube.

5. An evaporator for liquids containing l' solid substances comprising 'in combination l an upper receptacle and lower receptacle, a plurality oi' upright tubes of relatively small l diameters interposed between the said receptacles, nreans for heating said tubes, said I tubes openng directly into the body of liquid l contained in the upper receptacle and exthe upper and lower receptacles, the upper tending at an angle sharply acute with rel" lvuninterrupted direction toward the upper erence t0 the Vertical axis of the oncentreopening of the return tube.

tor in u. direction toward the upper openingg In testimony whereof have signed my of e return tube, a, return tube of relatively! neme to this specification-in the presence of 5 lerne dimensions tapering at the top Wholly two subscribing Witneses.

independent of and net cenneeted with the 'vertical pipes end spaced therefrom, the upi OSCAR FALLER" per openings olf the inclined tubes being so Witnesses: y leceted es to cause the liquid coming there ROBERT FALLER',

lo from to pass immediately in adownward ARNOLD GUisE. 

